A writer friend asked the question in her blog, "What's it like inside your mind?" and it started me thinking.
She spoke of characters from her stories, as did some of the comments, roaming around, falling out of bed, using items from her other stories, but none of this rang true for me.
The creative process fascinates me. An idea is triggered by some stimulus and my thoughts become restless, probing for connections, testing their strength, discarding weakness, in a logical progression...until, often quite abruptly, it will leap back to an earlier connection and follow an entirely new path to a totally unexpected result.
The closest physical analogy I can draw of the process comes from a description by Edward de Bono (I think he was writing of Water Logic). He postulated a beach full of octopi, dumped in a random order, their tentacles seeking connections and forming synapse-like patterns in a blind, gestalt-driven search. Thinking of any one octopus stimulates it, driving it to a more frenzied search, individual tentacles lashing, it's primitive mind cataloguing each contact and remembering their nature. This produces a ripple effect among the other octopi and soon they're all thrashing about until they reach a result that produces a feedback surge to the original octopus and a path is formed between the original idea and this new outcome.
Like all analogies, it fits only where it touches, but it gives me a good working model, and that's enough.
It's a great life.